Lower unit going down...

[Chris611]

I have spent the last hour or so reading old posts about Alpha I Gen II Outdrive (1996). It loses about a quarter cup of oil each time I go out. Has done it for a couple years. I don't see oil in the bellows, or any evidence of leaking. Boat is trailered to lake, so it sits on trailer when not in use. I have removed the drain plug in the lower unit and I get no water coming out. So it seems I am getting no water in the oil, but am losing oil. Any thoughts on where to check for leaks? If it's the shift linkage seal, will I see oil residue there with it on the trailer?<br /><br />Thanks<br />Chris

 

[Don S]

Re: Lower unit going down...

Assuming you have already drained the gear lube and done a pressure check which it passed, it very well may be the vertical shaft or the prop shaft or shift shaft that leaks only when spinning and the oil is warm.<br />If that is the case, short of dissassembly and resealing, I don't know what to tell you.

 

[Chris611]

Re: Lower unit going down...

Thanks for the reply. I am going to try and do a pressure test. Sounds like if I go to Wal-Mart and buy the oil lube pump, I can use that fitting to pressurize the unit to 10 psi? Is that the correct pressure? Sounds like if that passes do a vaccume test? Is it possible to have oil leak out and no water get in?<br /><br />Thanks<br />Chris

 

[KaGee]

Re: Lower unit going down...

RE: fitting... that's right, rob it from the kit... bought one last fall at Wally World for about $7. If you do a search, you will find examples of a home brew pressure checker.<br /><br />Also, if you start losing pressure, don't panic until you check the fitting and the vent screw.

 

[Chris611]

Re: Lower unit going down...

Thanks guys. I went to the local boat shop and bought the pump and some oil. I pulled the outdrive to take a look inside the bellows and also to set it on a stand to do the pressure check. I found something interesting. I am going to try and post some pics. Looks like there is a sludge in the void where the shifter link goes. Doesn't seem there shoud be oil or water in there. Also there seal on the shaft labeled "A" looks torn up. Didn't know if that seal was supposed to be water tight or not.<br /><br />

[/URL][/IMG] <br /><br />Here is the mating area:<br /><br />

[/URL][/IMG] <br /><br />When I removed the nuts that are above and below the nipple for the oil resevoir (blue arrows 1 & 2), oil was seeping out. The unit was pretty tight, I wonder if the gasket in that area had something wrong and was allowing oil from the nipple to drain into the shifter area where all the muck is? Can you guys give me your thoughts on what you see here. Also there are some gouges on the gasket surface where the previous boat shop pryed the halves apart when I first got the boat (blue arrows). Should I seal this area with some RTV?<br /><br />Thanks<br />Chris

 

[Don S]

Re: Lower unit going down...

Using your second picture, I can see what the problem is. Wrong gasket, silly-cone, and, as you know, the seal is bad at A.<br />Look at the gasket where it covers the seal around the gear lube monitor quick disconnect. Looks like someone cut a hole out of the wrong gasket to "Make It Work" which it didn't.<br />Get the proper gasket set for installing the drive to the bellhousing and change all the gaskets and orings. No sealer. except some adheisive to hold the seals in place. Silly-cone is not a sealer for boats.<br />There is a bushing kit that includes the seal to fix the problem at "A", check with your dealer for the proper one after you remove the old bushing.<br />Do you have a Merc service manual for your drive?

 

[Chris611]

Re: Lower unit going down...

Thanks Don S. I will get the proper gaskets and orings and try that. I have a Seloc manual. It's a little hard to follow and too generic, but right now it's all I have.<br /><br />Thanks<br />Chris

 

[Don S]

Re: Lower unit going down...

Then try this.<br /><br /> http://www.boatfix.com/merc/Servmanl/14/14cover.pdf

 

[Chris611]

Re: Lower unit going down...

Thanks for the link of the merc manual. Am I understanding right that the cavity where the shift linkage is should be free of oil and water. In otherwords the shift rod seal at "A" is leaking water and the gasket from the upper half to the bell housing is leaking oil into that cavity? <br /><br />Thanks<br />Chris

 

[Chris611]

Re: Lower unit going down...

I did a pressure test and the lower unit seems to be okay. Hopefully that means I was losing oil through the faulty shift shaft seals and also the bell housing to upper unit gasket. Also, there was no sign of water in the oil when I drained it. I am needing to order that seal kit (27-94996Q2). Called a few places and noone has them. Whats the best/quickest online shop? I have looked on stemtostern and they seem good, just wondered where others went. Just hoping to have the parts here by the weekend.<br /><br />Thanks<br />Chris

 

[Chris611]

Re: Lower unit going down...

I have the gaskets and seals and am ready to put it all back together. One issue, there is a gouge that runs from the top stud to the oil quick connect nipple on the transom mount. I am wondering what I need to do to the gouge to help ensure a good seal with the gasket? Any ideas would be greatly appreciated. Can I fill the gouge or use some sort of sealant?<br /><br />Thanks<br />Chris

 

[lilmandavis]

Re: Lower unit going down...

underwater grade marine sealant is what i use. NO SILICONE. 3m marine adhesive sealant 5200. its a polyurethane